Question

Resolva as equações a seguir.
a) 25x2= 16, sendo U = R.
b) 9x2-64=0, sendo U = R

Answer 1

Oie, Td Bom?!

a)

$25x {}^{2} = 16$

$25x {}^{2} - 16 = 0$

$x {}^{2} = \frac{16}{25}$

$x = ± \sqrt{ \frac{16}{25} }$

$x = ± \frac{4}{5}$

$S = \left \{ - \frac{4}{5} \: , \: \frac{4}{5} \right \}$

b)

$9x {}^{2} - 64 = 0$

$9x {}^{2} = 64$

$x {}^{2} = \frac{64}{9}$

$x = ±\sqrt{ \frac{64}{9} }$

$x = ± \frac{8}{3}$

$S = \left \{ - \frac{8}{3} \: , \: \frac{8}{3} \right \}$

Att. Makaveli1996